Clinical research represents the final stage of development for diagnostic imaging technologies. The quality of this research is of vital importance to the ultimate understanding of the clinical utility of the new property- based imaging modalities being developed in this Program. The Clinical Core will provide a single, centralized programmatic structure for initial clinical studies of the new imaging schemes. The Core will lead the recruitment of alternative imaging exam participants and the subsequent analysis/evaluation of the images and data derived form these encounters. The specific aims of the Clinical Core are to (1) develop a comfortable and efficient breast analysis methods and statistical measures for assessing images and data derived from alternative imaging exams relative to conventional clinical information, (3) identify correlations of the pathological findings with alternative imaging property values through targeted immunohistochemical and specimen image analysis studies in order to improve the understanding of the biophysical basis of image contrast, and (4) conduct a formal clinical study involving 150 patients being screened for breast to evaluate the interrelationships between the different properties measured on the same individual and provide initial assessments of the sensitivity and specificity of the alternative imaging modalities, used both singly and in combination, for discriminating between individuals. a) with normal findings and with abnormal findings using conventional clinical methods and radiological examinations, b) with and without a confirmed diagnosis of cancer. c) with alternative pathological findings, among the 75 patients with abnormal conventional findings undergoing biopsy. Clinical Core members will create a level of expertise in diagnostic radiology, clinical research, statistics, and data management that would be difficult to duplicate within individual Projects.